1. Field of the Invention
The present invention generally relates to surgical knot tying and cutting tools including a suturing or ligating aid or guide. More specifically, the invention relates to a surgical knot pusher for assisting with the placement and cutting of suture knots which have been tied extracorporeally during a surgical procedure.
2. Description of the Related Art
Surgical knot placement can be a very difficult task in situations where access to the surgical site is impeded or body fluids make the suturing material difficult to handle. Each of these problems can be particularly difficult to overcome in laparoscopic procedures where surgeons must tie surgical knots inside a small access port in a patient's body using only mechanical instruments. Devices for surgical knot tying are disclosed in U.S. Pat. Nos. 3,752,516; 4,602,635; 4,961,741; 5,087,263; and 5,176,691.
In a typical laparoscopic procedure, a suture loop is stitched between two portions of severed tissue inside of an access port in a patient's body with both ends of the suture material extending out of the access port. The surgeon then uses one end of the suture loop to tie a surgical slip knot around the other end of the suture loop. In order to facilitate tying, the slip knot is tied "extracorporeally," or outside of, the access port in the patient's body. A knot pusher can then be used to help advance the knot along one end of the suture loop while gently taking up the slack in the free end of the suture outside of the patient's body. This knot tying technique significantly reduces the time needed to close the incision and thus benefits both the patient and the surgeon.
Conventional knot pushers have included a V-shaped element, hook, or hole on the end of a long shaft. For example, a V-shaped element is included with a device available from Birtcher Solos while a device with a hole is available from Sharpe Endosurgical. Another approach uses a rod with a cone-shaped distal end having a hole which communicates between the front of the tip and a relieved section behind the tip. These devices have significant drawbacks in that they require the suture to either be threaded through-a small hole or to be securely held within the crotch of the V-shaped element. The former configuration has been found difficult to set up while, in the latter configuration, the suture material often falls out of the V-shaped element. Furthermore, none of these conventional devices include a mechanism for cutting excess suture material away from the knot after the suture has been fully tightened.